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Is there anyway to tell by the seedlings or by the young plant if they will be indeterminate or determinate tomatoes?

My kids planted tomato seeds at a community fair a weeks ago. They're growing and just formed their first set of true leaves. It would be really awesome if we can get at least one of the three plants in the SFG. The kids got a salsa recipe with it, so I'm guessing these won't be cherry tomatoes, but who knows?

We transplant tomatoes at the end of May here. Wanted to know for planning purposes, because I usually plant the indeterminate types.

Vaguely, in my experience There is a range from very determinate to very in-determinant anyways. Generally speaking the determinants have stockier stems and leaves/growth nodes are closer together up the stem. Be prepared for anything

I didn't even think to ask the woman with the seed packet at the fair, because the seeds we plant at those kinds of events never seem to grow, lol. The sticker on the cup just says "Tomato." The cilantro seeds they planted did not come up. This will be part of the surprise.

The only tomato I can identify is Brandywine. I saved seeds from one I bought at the Heirloom Exposition in September and bought a pack of seeds. Seedlings from both look alike, but so different from the other 9 varieties I grew from seeds.

You can tell the difference between dwarf varieties and regular varieties (determinate or indeterminate) at the seedling stage but I don't think there is a way to tell a determinate from an indeterminate at the seedling stage.

@jmsieglaff wrote:You can tell the difference between dwarf varieties and regular varieties (determinate or indeterminate) at the seedling stage but I don't think there is a way to tell a determinate from an indeterminate at the seedling stage.

So, how can you tell the difference between dwarf varieties and regular varieties (determinate or indeterminate) at the seedling stage?

Dwarf vs. determinate/indeterminate tomatoes can be told apart when true leaves begin appearing. If both kinds are grown in the same conditions, the dwarfs will have stockier stems and be about half the height when developing true leaves than regular (det/indet) tomatoes.